CVE-2026-55602GHSA-64MM-VXMG-Q3VJ
http-proxy-middleware `router` host+path substring matching allows Host-header-driven backend routing bypass
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 4.1.0, 3.0.6, 2.0.10
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: poc
- Automatable: yes
- Technical impact: partial
Summary
http-proxy-middleware is node.js http-proxy middleware. From 0.16.0 until 2.0.10, 3.0.6, and 4.1.0, http-proxy-middleware documents router proxy-table entries as host, path, or host+path selectors, but the host+path implementation uses unanchored substring matching on attacker-controlled request metadata. As a result, a crafted Host header that is only a superstring match for a configured host+path key can still route a request to an unintended backend. This vulnerability is fixed in 2.0.10, 3.0.6, and 4.1.0.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: poc · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- chimurai http-proxy-middleware
From 4.0.0 · fixed in 4.1.0; From 3.0.0 · fixed in 3.0.6; From 0.16.0 · fixed in 2.0.10
- http-proxy-middlewarenpm
From 3.0.0 · fixed in 3.0.6
- http-proxy-middlewarenpm
From 4.0.0 · fixed in 4.1.0
- http-proxy-middlewarenpm
From 0.16.0 · fixed in 2.0.10